The than bauk (sometimes 'thanbauk') is traditionally a witty saying or epigram. Like the ya du, it is of Burmese origin and revolves around the use of climbing rhyme.
It consists of three lines, each of which has four syllables. The last syllable of the first line, the third syllable of the second line and the second syllable of the third line all rhyme.
xxxa
xxax
xaxx
To extend the form, this pattern is either repeated in seperate stanzas, or, alternatively, a kind of chain of climbing rhymes can be formed.
xxxa
xxax
xaxb
xxbx
xbxc
xxcx
xcxd
Personally I found the ya du a lot more enjoyable. That, of course, is my excuse for not having finished an example of this form. However, it's a good way to brush up on your climbing rhyme, if that's what floats your boat.
In lieu of my own example, here's a relatively contemporary one by Tin Moe, which appears to follow slightly more relaxed rules than those outlined above:
Èthegyi (from The Great Guest, 1959)
Hsay leik lè to
Nei lè nyo bi
Nga go pyan po gya ba lei
Cigar's burnt down
The sun is brown
Will somebody take me home?
- translated by Anna Allott